princejeet :
You don't need 750w PSU . The 650w PSU is m everythingore than enough for water cooling & what u listed in ur rig.
Alright. I'm going with the 550w from Seasonic that anort posted, though. I love the fully modular design, I'm sure the cables have the proper length, and I know Seasonic are out of this world in their respective field.